The empty couple of pages

[Pupeno <pupeno@pupeno.com>]

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I'm using double.sided true and I get this result:
page [1]: Title of the book
page [2]: abstract and copyright
page [3]: empty
page [4]: empty
page [5]: table of contents...
Does anybody have a clue of what might be generating this couple of empty 
pages ? (I'm trying hard to reduce the emptyness of my book to the minimum).
Thank you.
- -- 
Pupeno: pupeno@pupeno.com - http://www.pupeno.com
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